It's a parenting milestone that isn't in any of the books - the first time you're caught "getting busy" by one of your kids.
Blogger Emma Lou Harris took to Facebook to describe the mortifying moment it happened to her and her husband - and her hilarious account will have you in stitches.
"There's an inevitable moment in every parent's life when your children catch a glimpse of something you'd much rather they didn't," Ms Harris begins, as she sets the "traumatising" scene.
"I'd had two full beers that night," writes the Irish mother-of-two, adding that her husband, Joe, had emptied the dishwasher without having to be asked.
This act of unprompted domestic heroism was the clincher. "I knew right then and there it was game on," Ms Harris writes. "Pants. Off!"
With their one-year-old and three-year-old put to bed in record time, the pair "hopped on straight down to sexy town".
"Things were getting heated," Ms Harris writes. "We were just getting to the bit of the act about half way through where you actually consider going professional and you wonder why you ain't teaching these kinda moves on some sort of intense weekend course for beginners."
It was so good, in fact, that Ms Harris notes, "we were JUST about to be reminded whyyyyyyyyy the HELL I ever put up with this bollox leaving his crap all over the house."
Until they heard the dreaded, "Mummmmyyyyyyy", that is.
"My panic sweat glands jump into emergency mode busting open like a military operation and my vagina zips itself up to my back immediately before I've even had a chance to turn my head," Ms Harris writes.
"I look up to see a moving smudge of colour in a 'my little pony' night gown rubbing its eyes and whinging," she continues. "I pray to the baby Jesus that we have a poltergeist and I also pray it's legally blind."
But it wasn't a poltergeist.
"In that same split second I hear a small girl scream," Ms Harris writes. "It's Joe. It was the noise accompanied by him leaping off me higher than a kangaroo hurdler while very nearly giving himself a home circumcision from the ceiling fan in the process."
Watching her husband in slow motion, Ms Harris writes that she saw "the anaconda swerving all over the place threatening to strangle me to death in the act".
"Seriously," she continues, "the thing nearly slapped me in the face and blackened the eyes off me on its jump up there."
Standing by the side of the bed, the couple saw their daughter, three-year-old Frankie.
And they had absolutely no idea how long she'd been there.
"She's rubbing her eyes," Ms Harris writes, "and momentarily I consider the fact that she may actually be trying to scratch them out."
After clarifying that Frankie had lost her dummy, and locating the rogue pacifier, the couple regrouped - staying awake all night "staring at the ceiling" and not saying one word.
"I don't know what she saw that night," Ms Harris writes. "I can't say for definite if she saw too much or if she saw anything at all.
"All I know is, if in the future, my poor poor innocent child ever comes to me and tells me she remembers a very vivid dream where two large warthogs were trying to give each other a hoosh over a wall or that two friggin tapers were playing an aggressive game of twister , well, I guess I'll have my answer."
And as for the traumatised couple?
"Myself and Joe are due to finish our Trauma Counselling sometime in the year 2045," Ms Harris writes.
Judging by the response to her post, Ms Harris and her husband aren't the only ones to have been caught in the act.
"You are not alone!" writes Lisa Brown. "My daughter shows no signs of trauma 4 years later now when she got a double dose of it. 'Why are you guys naked?' 'Um.. we're hot. It's so hot in here. Yeah that's it.' And she says 'Yeah I'm hot too' then sits on the opposite couch like she's gonna hang out and watch a movie with us as if nothing she saw was a big deal. My leg was up on the wall. Yep, that's how I normally sit. Complete with dad on top of me."
Other commenters, however, shared that the problem only gets worse as children get older - and know exactly what their parents are up to.
"I hate to break it to ya babe," writes Melissa George. "But believe me they will see, know and be aware of much MUCH more in due process.Teens are the very worst!! I use props, a computer chair between the bed and our door. Something like a sandal or shoe to jam under the bottom so you have those split 3 seconds to do the running man and hop outta bed.
Wondering how other parents make sexy time happen? Take a look at these tips.